Currently I have 2 in a 10 gallon and 1 in a bit smaller tank to lessen the aggression. When I initially put them all in the 10 gallon two of them immediately attacked the weaker one. I think the weaker one is injured because it is having trouble staying on the bottom, it keeps floating a little.
I know a lot of people keep the blue crayfish so I figure these can't be much different. They are happily munching on some food discs right now. They don't seem to go up to the surface so I'm not sure if feeding the floating foods would work, for now they are getting sinking pellets and discs.
Any advice on them?
They are all between 3.5"-4.5"
Here are some pictures (sorry about the quality, they don't appreciate the camera
):
